The present invention relates to apparatus and method for insuring the safe disposal of hypodermic needles in certain situations and for the prevention of the spread of blood borne diseases.
When a catheter is inserted into a patient, usually an arm, for the intravenous delivery of a fluid, a disposable needle passing through the catheter is utilized to make the puncture to permit entry of the tip of the catheter. The needle is then withdrawn leaving the catheter in place either for a direct hook up to the bottle of fluid to be delivered, or capped for later use. The needle, tipped with blood, is dropped into a container for disposal.
It has been found that for needles disposed of in this manner, there is a certain incidence of occurrences in which a hospital technician or other personnel receives a puncture from one of the used needles. With the developing concern over the transmission of AIDS, there is real interest in finding alternative and safer ways of disposing of such needles.
Also noted is that upon withdrawal of the needle from the catheter there is inevitably a certain amount of patient's blood spilled. This body may harbor certain viral or non-viral diseases and can be the source of exposure for other individuals caring for the patient.
In U.S. Pat. No. 3,306,290 there is taught a syringe containing a spring to retract automatically a needle.
U.S. Pat. No. 4,026,287 discloses a syringe in which the needle is retracted by having a plunger rod rotate to engage the piston attached to the needle so that the latter can be withdrawn in a positive manner.
U.S. Pat. No. 4,392,859 shows an injection gun for use with animals in which between injections the needle is put in contact with a sterilizing substance.
U.S. Pat. No. 4,507,117 discloses a syringe in which the plunger makes positive engagement with the needle piston after injection to permit withdrawal of the needle into the syringe.
U.S. Pat. No. 4,507,118 has an injection gun for use with animals which incorporates a sterilizing element to sterilize the needle between use. A spring is employed to retract the needle each time.
U.S. Pat. No. 4,542,749 teaches a syringe with automatic plunger return relying on either air compressed during injection to return the needle or a separate source of compressed fluid.
U.S. Pat. No. 4,592,744 teaches an arrangement for sheathing a needle after use in which the user of the syringe physically withdraws the latter which grasps and pulls the needle into the sheath.
The arrangements described in the patents above are either too complicated or expensive to be used as disposable items, or require that the user take positive action to effect the safe disposal of the needle, or are not applicable to the particular circumstances to which the present invention pertains.